Enter the text here that is the new abstract information for your application. This section must be no longer than 30 lines of text. Does living in a distressed neighborhood affect the health and long-term well-being of low-income adults? A large observational (non-experimental) literature in the social and medical sciences suggests the answer is yes. However, a more qualified answer comes out of our own research team's analysis of data from a unique randomized neighborhood mobility experiment known as Moving to Opportunity (MTO). The MTO demonstration used a randomized lottery to offer some public housing residents but not others the chance to relocate to less disadvantaged neighborhoods using a rental housing subsidy. MTO experimentally generated large differences in neighborhood characteristics for otherwise comparable groups of low-income, is proportionately minority families. From 2008-10, in-person survey data and biomarkers were collected by our team from 3,215 female adults in MTO. Our findings to date (published in New England Journal of Medicine and Science) show neighborhood environments do have important effects on health and well-being, but, contrary to previous research, not on adult self-sufficiency. While the MTO findings have received a great deal of scientific and media attention, their impact has been complicated by lingering methodological questions, as well as uncertainty about how to reconcile the findings of MTO with previous studies. We request support here to use the long-term MTO data to explore these methodological issues and: 1. Determine whether differences between MTO and previous observational studies can be explained by selection-biases with the latter, and the conditions under which non-experimental approaches can produce unbiased estimates. 2. Explore the role of interference in MTO as an explanation for differences in results with previous studies, by exploiting data on exact baseline addresses. 3. Examine whether differences across studies in findings can result from differences in neighborhood change treatment dose, by testing whether neighborhood effects on adult outcomes are linear or non-linear with respect to specific neighborhood conditions using an instrumental variables approach. 4. Examine if there is important heterogeneity in neighborhood effects on adult self-sufficiency, health, and well-being by the characteristics of MTO individuals or their families.